Foreign observers of Egypt's first real leadership contest will be unable to say whether the process is free and fair because their movements are being restricted by election authorities, one of the groups supposed to be monitoring the vote said.

The election to decide who succeeds ousted President Hosni Mubarak after more than a year of interim army rule begins in a week, but international observers have not received the documents they need to be witnesses, said Sanne van den Bergh, field office director at the US-based Carter Center.

"Even three weeks ago would be quite late. Normally we witness candidate nominations, voter registration, certainly the campaign period. We cannot comment on the entire process if we have missed those aspects," she told Reuters in an interview.

The process of choosing a head of state for the most populous Arab country will help define the success of street revolts that last year swept a region long ruled by monarchs and military strongmen.

With Egypt's interim army rulers pledging to hand power to the winner of the two-stage election, citizens accustomed to Mubarak's tightly-managed politics are now being courted through impassioned television debates and well-funded campaigns reaching deep into the provinces.

But the build-up has been marred by last-minute disqualifications of some leading candidates that fueled suspicions among critics of the ruling generals of high-level manipulation.